Greetings, Mabar2000, and welcome. You asked:

<<I am a US Citizen working abroad for 5 years now, at a foreing non-profit institution. Although in the past I had established retirement plans with previous employers(Prudential, annuity program, and a Vangard IRA rollover) I have not contributed to those and I do not have a current retirement plan with my present employer. Does somebody know if I would qualify for a Keogh or an H10 plan?. Would the contributions be tax deferred? .>>

If you have earned income (i.e., job wages) that you claim for income tax purposes (i.e., you have not excluded it as foreign job income), then you may make a deductible contribution of up to $2K annually to an IRA. However, you are not eligible for one of the self-employed programs like a Keogh, SEP or SIMPLE because you are not self-employed and the foreign entity for which you work may not establish such a plan for you.

Regards..Pixy